# Copyright (C) 2021 Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Test a binary that uses MTE and exercise various MTE-related scenarios.

global hex
global decimal

# Return TAG in hex format with no leading zeroes.
proc get_hex_tag { tag } {
    return [format "%x" $tag]
}

# Return TAG in the NN format where N is 4 bits of the byte.
proc get_tag_nn { tag } {
    return [format "%02x" $tag]
}

# Return the address of PTR with a tag of TAG.
proc get_tagged_ptr { tag ptr } {
  set addr [get_hexadecimal_valueof $ptr -1]
  return [get_valueof "/x" \
	      "${addr} & (0xf0ffffffffffffff) | ((unsigned long) ${tag} << 56)" \
	      "0" "fetch pointer ${ptr} with tag ${tag}"]
}

# Return the logical TAG from PTR.
proc get_ltag_from_ptr { ptr } {
  set addr [get_hexadecimal_valueof $ptr -1]
  return [get_valueof "/x" "${addr} >> 56 & 0xf" -1 \
		      "fetch tag from pointer ${ptr}"]
}

if {![is_aarch64_target]} {
    verbose "Skipping ${gdb_test_file_name}."
    return
}

standard_testfile
if { [prepare_for_testing "failed to prepare" ${testfile} ${srcfile}] } {
    return -1
}

if ![runto_main] {
    return -1
}

# Targets that don't support memory tagging should not execute the
# runtime memory tagging tests.
if {![supports_memtag]} {
    unsupported "memory tagging unsupported"
    return -1
}

gdb_breakpoint "access_memory"

if [gdb_continue "access_memory"] {
    return -1
}

# Fetch a known pointer to an area mapped with PROT_MTE.
set tagged_ptr_symbol "tagged_ptr"
set tagged_ptr_addr [get_hexadecimal_valueof $tagged_ptr_symbol -1]

if {$tagged_ptr_addr == -1} {
    unresolved "unexpected pointer or tag value"
    return -1
}

# Fetch a known pointer to an area not mapped with PROT_MTE.
set untagged_ptr_symbol "untagged_ptr"
set untagged_ptr_addr [get_hexadecimal_valueof $untagged_ptr_symbol -1]

if {$untagged_ptr_addr == -1} {
    unresolved "unexpected pointer or tag value"
    return -1
}

with_test_prefix "literals" {
    # Test inspecting an allocation tag from a pointer to a memory area that
    # is not mapped with PROT_MTE.
    set msg "Address ${untagged_ptr_addr} not in a region mapped with a memory tagging flag\."
    gdb_test "memory-tag print-allocation-tag ${untagged_ptr_addr}" $msg \
	     "memory-tag print-allocation-tag with an untagged address"

    gdb_test "memory-tag set-allocation-tag ${untagged_ptr_addr} 1 00" $msg \
	     "memory-tag set-allocation-tag with an untagged address"

    set addr_tagged 0
    set addr_tagged_valid 0

    # Test setting and showing the logical tags for a literal address.
    for {set i 0} {$i < 32} {incr i} {
	with_test_prefix "tag ${i}" {
	    set addr_tagged [get_tagged_ptr $i ${tagged_ptr_addr}]
	}

	set tag_hexnz [get_hex_tag [expr $i % 16]]
	gdb_test "memory-tag print-logical-tag ${addr_tagged}" \
		 " = 0x${tag_hexnz}" \
		 "print-logical-tag with tag ${i}"

	set tag_hexnn [get_tag_nn $i]
	gdb_test "memory-tag with-logical-tag ${addr_tagged} ${tag_hexnn}" \
		 " = \\(void \\*\\) ${addr_tagged}" \
		 "with-logical-tag with tag ${i}"
    }

    set atag_msg "Allocation tag\\(s\\) updated successfully\."
    # Test setting and showing the allocation tags.
    for {set i 0} {$i < 32} {incr i} {

	set tag_hexnn [get_tag_nn $i]
	gdb_test "memory-tag set-allocation-tag ${tagged_ptr_addr} 1 ${tag_hexnn}" \
		 $atag_msg \
		 "set-allocation-tag with tag ${i}"

	set tag_hexnz [get_hex_tag [expr $i % 16]]
	gdb_test "memory-tag print-allocation-tag ${tagged_ptr_addr}" " = 0x${tag_hexnz}" \
		 "print-allocation-tag with tag ${i}"
    }

    # Test tag mismatches.
    with_test_prefix "tag mismatches" {
	for {set i 0} {$i < 32} {incr i} {

	    # Set the allocation tag to a known value.
	    set tag_hexnn [get_tag_nn $i]
	    gdb_test "memory-tag set-allocation-tag ${tagged_ptr_addr} 1 ${tag_hexnn}" \
		     $atag_msg \
		     "set-allocation-tag with tag ${i}"

	    set atag_hexnz [get_hex_tag [expr $i % 16]]

	    # Validate that the logical tag matches the allocation tag.
	    with_test_prefix "tag ${i}" {
		set addr_tagged [get_tagged_ptr $i ${tagged_ptr_addr}]
	    }

	    gdb_test "memory-tag check ${addr_tagged}" \
		     "Memory tags for address $hex match \\(0x${atag_hexnz}\\)\." \
		     "check match with tag ${i}"

	    # Get a pointer with the logical tag that does not match the
	    # allocation tag.
	    set ltag [expr $i + 1]
	    with_test_prefix "fetch mismatch tag ${i}" {
		set addr_tagged [get_tagged_ptr $ltag ${tagged_ptr_addr}]
	    }

	    # Validate that the logical tag does not match the allocation
	    # tag.
	    set ltag_hexnz [get_hex_tag [expr [expr $i + 1]% 16]]
	    gdb_test "memory-tag check ${addr_tagged}" \
		     "Logical tag \\(0x${ltag_hexnz}\\) does not match the allocation tag \\(0x${atag_hexnz}\\) for address $hex\." \
		     "check mismatch with tag ${i}"
	}
    }
}

with_test_prefix "symbolic" {
    # Test inspecting an allocation tag from a pointer to a memory area that
    # is not mapped with PROT_MTE.
    set msg "Address ${untagged_ptr_addr} not in a region mapped with a memory tagging flag\."
    gdb_test "memory-tag print-allocation-tag ${untagged_ptr_symbol}" $msg \
	     "memory-tag print-allocation-tag with an untagged address"

    gdb_test "memory-tag set-allocation-tag ${untagged_ptr_symbol} 1 00" $msg \
	     "memory-tag set-allocation-tag with an untagged address"

    # Test setting and showing the logical tags for a literal address.
    for {set i 0} {$i < 32} {incr i} {
	set addr_tagged 0

	with_test_prefix "tag ${i}" {
	    set addr_tagged [get_tagged_ptr $i ${tagged_ptr_addr}]
	    gdb_test_no_output "set variable ${tagged_ptr_symbol} = ${addr_tagged}" \
			       "update value of symbol ${tagged_ptr_symbol}"
	}

	set tag_hexnz [get_hex_tag [expr $i % 16]]
	gdb_test "memory-tag print-logical-tag ${tagged_ptr_symbol}" \
		 " = 0x${tag_hexnz}" \
		 "print-logical-tag with tag ${i}"

	set tag_hexnn [get_tag_nn $i]
	gdb_test "memory-tag with-logical-tag ${tagged_ptr_symbol} ${tag_hexnn}" \
		 " = \\(void \\*\\) ${addr_tagged}" \
		 "with-logical-tag with tag ${i}"
    }

    # Reset the tagged ptr to its original value
    gdb_test_no_output "set variable ${tagged_ptr_symbol} = ${tagged_ptr_addr}" \
		       "reset ${tagged_ptr_symbol} to ${tagged_ptr_addr}"

    set atag_msg "Allocation tag\\(s\\) updated successfully\."
    # Test setting and showing the allocation tags.
    for {set i 0} {$i < 32} {incr i} {

	set tag_hexnn [get_tag_nn $i]
	gdb_test "memory-tag set-allocation-tag ${tagged_ptr_symbol} 1 ${tag_hexnn}" \
		 $atag_msg \
		 "set-allocation-tag with tag ${i}"

	set tag_hexnz [get_hex_tag [expr $i % 16]]
	gdb_test "memory-tag print-allocation-tag ${tagged_ptr_symbol}" \
		 " = 0x${tag_hexnz}" \
		 "print-allocation-tag with tag ${i}"
    }

    # Test tag mismatches.
    with_test_prefix "tag mismatches" {
	for {set i 0} {$i < 32} {incr i} {

	    # Set the allocation tag to a known value (0).
	    set tag_hexnn [get_tag_nn $i]
	    gdb_test "memory-tag set-allocation-tag ${tagged_ptr_symbol} 1 ${tag_hexnn}" \
		     $atag_msg \
		     "set-allocation-tag with tag ${i}"

	    set atag_hexnz [get_hex_tag [expr $i % 16]]

	    # Validate that the logical tag matches the allocation tag.
	    with_test_prefix "tag ${i}" {
		set addr_tagged [get_tagged_ptr $i ${tagged_ptr_addr}]
	    }

	    with_test_prefix "tag ${i}" {
		gdb_test_no_output "set variable ${tagged_ptr_symbol} = ${addr_tagged}" \
				   "set ${tagged_ptr_symbol} to a matching logical tag"
	    }

	    gdb_test "memory-tag check ${tagged_ptr_symbol}" \
		     "Memory tags for address $hex match \\(0x${atag_hexnz}\\)\." \
		     "check match with tag ${i}"

	    # Get a pointer with the logical tag that does not match the
	    # allocation tag.
	    set ltag [expr $i + 1]
	    with_test_prefix "fetch mismatch tag ${i}" {
		set addr_tagged [get_tagged_ptr $ltag ${tagged_ptr_addr}]
	    }

	    with_test_prefix "tag ${i}" {
		gdb_test_no_output "set variable ${tagged_ptr_symbol} = ${addr_tagged}" \
				   "set ${tagged_ptr_symbol} to a mismatching logical tag"
	    }

	    # Validate that the logical tag does not match the allocation
	    # tag.
	    set ltag_hexnz [get_hex_tag [expr [expr $i + 1]% 16]]
	    gdb_test "memory-tag check ${tagged_ptr_symbol}" \
		     "Logical tag \\(0x${ltag_hexnz}\\) does not match the allocation tag \\(0x${atag_hexnz}\\) for address $hex\." \
		     "check mismatch with tag ${i}"
	}
	# Reset the tagged ptr to its original value
	gdb_test_no_output "set variable ${tagged_ptr_symbol} = ${tagged_ptr_addr}" \
			   "reset ${tagged_ptr_symbol} to ${tagged_ptr_addr}"
    }
}

# Test the memory tagging extensions for the "print" command.
with_test_prefix "print command" {
    set untagged_ptr [get_tagged_ptr 0 ${tagged_ptr_addr}]

    with_test_prefix "fetch ltag" {
	set ltag [get_ltag_from_ptr ${tagged_ptr_addr}]
    }

    if {$ltag == -1} {
	unresolved "unexpected tag value"
	return -1
    }

    set atag [expr [expr $ltag + 1] % 16]
    set atag_hexnn [get_tag_nn $atag]

    gdb_test "memory-tag set-allocation-tag ${tagged_ptr_symbol} 1 ${atag_hexnn}" \
	     $atag_msg \
	     "make atag and ltag different"

    set atag_hexnz [get_hex_tag $atag]
    gdb_test "p/x ${tagged_ptr_symbol}" \
	[multi_line \
	    "Logical tag \\(${ltag}\\) does not match the allocation tag \\(0x${atag_hexnz}\\)\." \
	    "\\\$\[0-9\]+ = ${untagged_ptr}"] \
	    "show tag mismatch"
}

# Test the memory tagging extensions for the "x" command.
with_test_prefix "x command" {

    # Check if the allocation tags match what we expect.
    gdb_test "x/gxm ${tagged_ptr_symbol}" \
	[multi_line \
	    "<Allocation Tag $hex for range \\\[$hex,$hex\\)>" \
	    "$hex:\[ \t\]+$hex"] \
	"outputs tag information"

    # Also make sure no tag information is output for memory areas without
    # PROT_MTE mappings.
    gdb_test "x/gxm ${untagged_ptr_symbol}" \
	     "$hex:\[ \t\]+$hex" \
	     "does not output tag information"
}

# Validate the presence of the MTE registers.
foreach reg {"tag_ctl" } {
    gdb_test "info registers $reg" \
	     "$reg\[ \t\]+$hex\[ \t\]+$decimal" \
	     "register $reg available"
}

# Run until a crash and confirm GDB displays memory tag violation
# information.
gdb_test "continue" \
    [multi_line \
	"Program received signal SIGSEGV, Segmentation fault" \
	"Memory tag violation while accessing address $hex" \
	"Allocation tag $hex" \
	"Logical tag $hex\." \
	"$hex in access_memory \\(.*\\) at .*" \
	".*tagged_ptr\\\[0\\\] = 'a';"] \
	 "display tag violation information"

# Restart to execute the async tag fault test.
with_test_prefix "async" {
    if ![runto_main] {
	return -1
    }

    gdb_breakpoint "access_memory"

    if [gdb_continue "access_memory"] {
	fail "could not run to tagged memory test function"
	return -1
    }

    # Force a tag fault.
    gdb_test "memory-tag set-allocation-tag tagged_ptr 1 05" \
	     $atag_msg \
	     "make atag and ltag different"

    # Force the tag fault to be async.
    gdb_test_no_output "set \$tag_ctl=0x7fff5" "set tag_ctl to async"

    # Run until a crash and confirm GDB displays memory tag violation
    # information for async mode
    gdb_test "continue" \
	[multi_line \
	    "Program received signal SIGSEGV, Segmentation fault" \
	    "Memory tag violation" \
	    "Fault address unavailable\." \
	    "$hex in .* \\(.*\\) .*"] \
	    "display tag violation information"
}